Lipases are widely used in esterification of various carboxylic acids such as fatty acids with alcohols such as monoalcohols and polyalcohols, transesterification between esters of several carboxylic acids, and the like. Among them, the transesterification reaction is an important technology not only as method for modifying animal and vegetable fats and oils but also as method for producing esters of various fatty acids such as sugar esters and steroids. When a lipase, which is a fat and oil hydrolase, is used as a catalyst in the above reactions, the transesterification reaction can be conducted under the mild condition, i.e. at room temperature to about 70° C. Therefore, the reactions using a lipase can better inhibit side reactions and reduce energy costs as compared with the conventional chemical reactions. In addition to it, since a lipase as a catalyst is a natural product, it is highly safe. Further, intended compounds can be effectively produced by using a lipase due to the substrate specificity and positional specificity thereof.
In order to evenly disperse such lipase in an oily raw material and to conduct transesterification in high activity, the technology has been developed comprising the steps of immobilizing a lipase to a carrier, grinding the immobilized lipase, and using the same (Patent Literature 1). However, a lipase sometimes causes allergic symptoms due to contact thereof to the skin or the suction thereof by breathing. In the production of an immobilized lipase powder composition, a lot of dust is generated in the step of grinding an immobilized lipase and, as a result, allergic symptoms are concerns. Thus, there is need to ensure safety of workers.
Patent Literature 1 WO 2006/132260 A